Michael Lutz INSPIRE MIG-T meeting #38 Ghent 28-29 March 2017 Proposal for a new MIWP action to improve the usability of INSPIRE (GML) data Michael Lutz INSPIRE MIG-T meeting #38 Ghent 28-29 March 2017

The issue INSPIRE data encoded according to the current schemas can be downloaded and viewed, but simple use (visualisation, simple joins, visual overlays, spatial search, …) is difficult in standard GIS clients, mainly because of (complex) INSPIRE xml schemas xml schema complexity reflects complexity of conceptual UML models (because of automatic generation according to the UML-to-GML encoding in D2.7 Encoding Guidelines) Most existing clients (e.g. GDAL/OGR OS library) consumes and writes flat data structures Proposed solutions create alternative simplified schemas for basic data exchange and direct visualisation in standard GI tools encourage better support of the default schemas by vendors

Simplification of xml schemas Proposals are already implemented in projects (ELF), MS (e.g. Danish AM example) and tools (e.g. ShapeChange) But currently no agreed encoding rule for creating such simplified schemas based on the requirements of the IRs This should be mainly address cross-cutting aspects (e.g. how to flatten recurring complex types, multiplicities, voidable properties) Also consider theme-specific requirements where appropriate Conceptual model current UML-to-XML rules alternative UML-to-XML rules Type-A att-A1 Type-B att-B1 att-B2 att-A2 Type-C att-C1 att-C2 prop-A3 link-to-D Type-D … Type-A att-A1.B1 att-A1.B2.1 att-A1.B2.2 att-A2.C1 att-A2.C2 prop-A3 link-to-D Type-D …

Out of scope: Simplification of conceptual model Simplification of / changes to the conceptual model is out-of-scope for the proposed action If there is a need for such simplification, this should be discussed in 2016.4 sub-group and the Thematic Clusters Conceptual model Updated conceptual model simplification of conceptual model UML-to-XML rules (D2.7) Type-A att-A1 Type-B att-B1 att-B2 att-A2 Type-C att-C1 att-C2 prop-A3 link-to-D Type-D … Type-A att-A1 Type-B att-B1 att-B2 att-A2 Type-C att-C1 att-C2 prop-A3 link-to-D Type-D …

Better client support for complex GML Some vendors and projects have also already started to improve the support for GML e.g. QGIS plugin for complex features To support other projects / tools to improve the support, the subset of XML schema (and GML) that is required in INSPIRE and for specific INSPIRE themes should be analysed and documented

Proposed actions – alternative schemas Draft alternative encoding rule Collect examples for simplified schemas (and the underlying use cases) from MS representatives and experts through the TC platform and MIWP-14 sub-group Create a repository of possible simplification rules to be applied Draft an alternative encoding rule that meets the requirements of the IRs (to be included in D2.7) If necessary propose how the mapping from the conceptual to the implementation model should be explicitly represented in UML

Proposed actions – alternative schemas Develop draft schemas for selected themes Draft additional simplified schemas for selected application schemas based on proposed encoding rule Review and testing, in collaboration with thematic communities (through the Thematic Clusters platform and MIWP-14 sub-group) Update encoding rules based on feedback from step 2 Develop a proposal for linking simplified and complete xml schemas in download services Propose agreed simplified schemas as alternative encodings to be included in the relevant data specifications

2. Better client support for complex GML Analyse which GML/XML schema aspects are actually being used in INSPIRE schemas, e.g. which themes use only SF, level 0 or which geometry types are used Analyse support for the required aspects are supported in existing clients, including the popular GDAL/OGR open source library (that is underlying most OS and proprietary client solutions) Discuss with the open source community and commercial vendors, how to improve client support for GML

Outcomes Repository of possible simplification rules Proposals for an update of D2.7 Encoding Guidelines Proposals for additional simplified schemas for selected application schemas Table of GML/XML schema aspects actually being used in INSPIRE schemas

Organisational set-up Work to be carried out by JRC, with support from a contractor Support from MS and thematic experts is crucial ( TC platform, MIG-T, 2016.1 sub-group) examples, testing and feedback Organise dedicated workshops (kick-off and feedback)? Need for a sub-group? How to involve vendors and users?